Removable counter-weight



Jan. 21, 1958 G. DAVIS REMOVABLE COUNTER-WEIGHT v 3 Sheets-Sheet 1 Filed Oct. 5, 1954 IN VEN TOR. GEORGE DAVIS ATTY.

. v"Il Jan. 21, 1958 G. DAVIS REMovABLE COUNTER-WEIGHT s sheets-sheet 2 Filed Oct. 5, 1954 FIG. 3

FIG. 2

INVENTOR.

GEORGE DAVIS BVM :l

Jan. 21, 1958 G. DAVIS REMOVABLE COUNTER-WEIGHT Filed oct. 5, 1954 5 Sheets-Sheet 3 United 2,82%,555 Patented Jan. 21, 1958 REMOVABLE COUNTER-WEIGHT George Davis, Benton Harbor, Mich.

Application October 5, 1954, Serial No. 464,658

9 Claims. (Cl. 214-142) My present invention relates generally to removable counterweights, and, more particularly, to removable multisection counterweights for truck cranes and similar industrial vehicles.

One form of vehicle with which my present invention has application is a truck crane comprised of a mobile main frame having a drivers cab at the forward end thereof and a rotatable crane supporting platform intermediate of the ends thereof. The platform supports a boom assembly, boom hoist mechanism and an operators cab. So that boom assembly, and any attachment at the outer end thereof, may withstand substantial loading, the boom hoist mechanism, together with additional counterweight, is generally mounted on the rotatable platform at the end opposite that to which the boom assembly is mounted.

VIt should be quite apparent that as the loading on the boom assembly is increased, the weight of the counterweight must be correspondingly increased. And, where relatively heavy loading is involved, the entire weight of the truck crane may become so great as to unduly load the vehicle drive means when the crane Ais being driven from one location to another. Moreover, in this situation, the'weight of the truck kcrane may eX- ceed that permitted on highways.

It is an object of my present invention to provide a counterweight for truck means and similar industrial vehicles which may be selectively removed 'from the crane supporting platform and reinstalled at will.

it is another object of my present invention to provide a multi-section removable counterweight with the sections being removable individually or in groups `so that the effective weight of the counterweight may be selectively and conveniently varied.

It is a further object of my present invention to provide a counterweight as noted wherein the installation and removal is facilitated by the boom hoist mechalnism of the truck crane.

Now in order to acquaint those skilled in the art with the manner of constructing and using removable counterweights in accordance with the principles of my present invention, l shall describe in connection with the accompanying drawings a preferred embodiment of my invention.

In the drawings:

Figure l is a side elevational view of a truck crane in which my present invention maybe embodied;

Figure 2 is a transverse sectional view taken substantially along the line 2 2 in Figure 1, looking inthe direction indicated by the arrows, and shows the multivsection removable counterweight, 'and the supporting frame means therefor, of my present invention;

Figure 3 is a plan view Yof the counterweight struc- Yture shown in Figure 2;

Figure 4'is a transverse 'sectional view corresponding to Figure 2 butshows three-sections of the counterweight removed from the supporting structure therefore; `and Figure 5 is a transverse sectionalview corresponding to Figure 2 but shows all of the sections of the counterweight removed from the supporting structure therefor.

Referring now to the drawings, there is shown in Figure l a truck crane comprising a longitudinally eX- tending mobile main frame 10 which is supported on a plurality of Wheels 12 and which has a drivers cab 14 at the forward end thereof. The forward pair of Wheels 12 are used for steering and the rear pairs of wheels 12 are driven by prime mover means (not shown) a1'- ranged adjacent the drivers cab 14. A yhorizontal boom or crane supporting platform 16 is rotatably supported at one end on the main frame 10 intermediate of the ends of the latter, and the platform or turntable 16 supports at its pivoted end a vertically swingable boom assembly 18 and an operators cab 20. The outer end of the boom assembly 18 may be provided with a trench hoe assembly 21, as shown, a crane hook, or other conventional attachments well known in the art. Suitable boom hoist mechanism, including prime mover drive means, is mounted Within an enclosure member 22 on the turntable 16 at the end opposite that to which the boom is mounted. The boom hoist mechanism serves to effect the required movements of the boom assembly 18 during operation of the latter and comprises a worm driven hoist drum 24 and a power driven cable 26, preferably of wire, extending between the drum 24 and the boom assembly 1S. The cable 26 is adapted to be released from the boom assembly 18 and used in connection with the counterweight means of my present invention in a manner to be described hereinafter. A detailed showing and description of the boom hoist mechanism has not been included in the present application because it is of conventional construction which is known to those skilled in the art and because it does not form part of my present invention.

As shown in Figures 2 and 3, the rotatableplatform 16 includes a pair of parallel angle frame members 36 which, at their ends opposite to the `pivotal mounting of the platform 16, are secured by means of a plurality of bolts 38 to a transverse brace member .40 having a central opening 42 formed therein. yMounted above the transverse member 40 withinthe enclosure member 22 is counterweight mechanism comprising the removable counterweight, and the supporting structure-therefor, of my present invention which I shall now describe in detail.

The counterweight supporting structure or framemeans is of generally inverted U-shape and comprises spaced vertical side bars 44 which at their lower ends extend into the opening 42 in the transverse member 40 and are secured, as by welding, to the facing sides of the angle frame members 36. The upper ends .of the side bars 44 are interconnected by an angle brace 46 which supports the one end of spaced brackets v48 that project toward the boom assembly 18. Ther brace V46 and brackets 48 are preferably welded in position. Bolted in the free ends of the brackets 43 is a shaft 50 upon which a pulley or sheave 52 is rotatably mounted. The pulley 52 is yso arranged that a transverse vertical plane tangent to the edge thereof adjacent the brace 46 lies Ybetween the transverse vertical planes of the Vedges ofthebars 44. A transversely extending inverted C-shaped `suspension .member S4 is secured at its ends, for example by welding, to the facing sides of the bars 44 intermediate ofthe ends thereof. These connections of the suspension member 54 with the bars 44 are reinforced by angle corners 56 and gusset plates 58 which may be joined by welding.

Bolts 60 are employed for fastening the angle corners 56 4extending downwardly therethrough are relatively long-` bolts 62, the'heads of which rest on the angle corners 56. The bolts 62 further project through aligned openings formed in a plurality (e. g., six) of vertically stacked plates 64 which constitutethemulti-section removable counterweight of my present invention. As will be presently describedthe effective weight of the counterweight may be varied by changing the number of plates 64 secured Within the supporting structure. The plates 64 are maintained as a group in assembled relation on the bolts 62, as shown in Figure 2, by nuts 66 threaded onto the lower ends of these bolts. The plates 64 are of generally rectangular shape and may have the c orners thereof rounded as shown in Figure 3. Furthermore, so as to facilitate mounting and removal of the plates 64, the ends of the plates may be shaped with Vcut-outs that conform to the cross-sectional vshape of the bars 44 so that they may be guided on the latter. It is to be further noted that the plates 64 are arranged vertically above the opening 42 in the transverse bracermember 40 and are adapted to be passed through this opening during their installation and removal.

Horizontal blind openings 68 are formed in the ends of each plate 64 and are adapted to be aligned with openings 70 formed in the bars 44. The lowermost openings 70 also extend through the angle frame members 36, as shown in Figure 2. When the openings 68 in any particular plate 64 are aligned with any pair of horizontally aligned openings 70, and pins 7 2 are properly inserted in these aligned openings, the plate is locked against vertical movement relative to the counterweight supporting structure. The locked plate, incidentally, will also support the plates, if any, which are above it, independently of the bolts 62.

Should it be desired to remove several or `all of the counterweight sections or plates 64, in the event that light loads are to be handled or the truck crane is to be moved over highways, the turntable 16 is rotated to a position where the counterweight sections and supporting structure over-hang or project beyond the main frame of the'truck crane. 'With the platform 16 in this position, it is possible to raise and lower the counterweight sections 64 to and from the supporting frame means b'y means of the power driven cable 26.

If the lower three plates 64, for example, are to be re- Y moved, the power driven cable 26 is disconnected from the bottom assembly 18 and is trained over the pulley 52 above the counterweight sections. In other words, the cable 26 is moved from the solid line position shown in Figure lV to the dash line position. The downwardly extending portion of the cable 26 is fed through the central openings 67 formed in the plates 64 and the lower end thereofv is looped about an inverted teardrop-shaped member 74. The lower end of the cable 26 and the member 74 are then drawn upwardly Within a generally truncated cone-shaped collar member 76 abutting the lower plate 64 as shown in Figure 2. As tension is applied to the cable 26, the lower end thereof, together with the member 74, is locked or secured within the collar 76 and is then capable of supporting the sections of the counterweight.

In addition, as tension is applied to the cable 26, the Weightl of the counterweight sections 64 is removed from the nuts 66 at the lower ends of the suspension bolts 62 and -these nuts are then Unthreaded. After the nuts 66 have been removed from the bolts 62, the entire Vgroup of counterweight sections 64 are juggled vertically, for example through movement of the cable 26, until the blind openings 68 are aligned with the openings 70 in the bars 44 and the pins 72 are inserted in the aligned openings at the opposite ends of the third plate 64 from the top ofthe group for selectively locking this section to the supporting frame means. Then the cable 26 is played out and the three plates 64 lying below the locked plate are lowered from the frame means through the opening 42 inthe ,'transversemember 40 to the ground, as shown in Figure 4 x 4. As the plates 64 are lowered, the pins 72 serve to hold the top three plates in position.

To release the lower three plates from the cable 26,' tension on the cable is relieved and the member 74 and collar 76 removed. The cable is then drawn through the central openings 67 in the lower plates and rearranged with the member 74 and collar 76 adjacent the lower of the upper three plates.A At this'point tension is applied to the cable, the pins 72 are removedfrom the blind openings 68 and the plates drawn tight against the suspension member S4. The nuts 66 are threaded on the bolts 62 against the lower of the upper three plates and finally the cable is released, in the manner described. Thebolts boom assembly 18. It is to be understood that bolts 62 l of various lengths may be used to Vconform to the vthickness of the number of kplates secured to the frame means at any particular time.

In the event that all of the counterweight sections64 must beremoved from the truck crane, the pin members 72 are removed from the bars 44. Consequently, after the lower end of the cable 26, together with the member 74, is locked within the cone collar 76 and the nuts 66 are removed Vfrom the bolts 62, all of the counterweight sections 64 will follow the cable 26 downwardly as it is lowered, as shown in Figure 5. After the cable'26 is removed from the sections 64, the truck craneis ready to be driven over the highways.

Installation of one or more counterweight sections 64 is elected in a manner opposite to that just described. That is, the cable 26 is passed through the central openings 67 in the plates to be inserted in the counterweight supporting structure, locked within the cone collar 76, and drawn upwardly, with the cut-outs and the bolt openings in the'plates 64 being aligned respectively with thebars 44 and the bolts 62. With the plates 64 drawn up intothe the cable 26 isreleased from locking engagement with the cone collar 76 and member V74. Finally, the cable is withdrawn from the plates 64 and reattached to the boom assembly 18 for again operating the latter.

It will be understood from the foregoing description that since the cable of the boom hoist mechanism is used for installing and removing the counterweight sections, as described, no separate and additional hoist means has to be incorporated in the truck crane for performing such operations. Thus, the initial cost of the counterweight mechanism of my present invention is maintained at a minimum. In addition, maintenance costs remain low.

Now while I have shown and described what I believe to be a preferred embodiment of my present invention, it will be understood by those skilled in the art that various rearrangements and modications may be made therein without departing from the spirit and scope of my invention.

I claim:

1. Counterweight mechanism comprising frame means, a plurality of counterweight sections, first means for securing said sections as a group to said frame means in vertical stacked relation, second means for selectively locking one of said sections yto saidframe means, and

carried by the vehicle, a plurality of counterweight sec-l tions, iirst means for securing said sections as a group to said frame means -in vertical stacked relation, second meansfor selectively lockingL one of lsaid sections to said frame means, and power operated cable means carried 4by the vehicle for lowering the Ysections lying below the locked section from said frame means when said rst means is rendered inoperable.

3. For use in a vehicle, counterweight mechanism comprising frame means carried by the vehicle, a plurality of counterweight sections, power operated cable means carried by the vehicle and operable to raise and lower said counterweight sections to and from said frame means, means for selectively locking one of said sections to said frame means after the sections have been raised to the latter, said power operated cable means being operable to lower the sections lying below the locked section from said frame means, and selectively operable means for securing the sections retained in said frame means to the latter whereby said power operated cable means may be released for other operations when not employed for raising or lowering said sections.

4. For use in a vehicle, counterweight mechanism comprising generally inverted U-shaped frame means carried by the vehicle and having vertical side bars, a plurality of counterweight sections shaped to be guided on said side bars, pulley means at the upper end of said frame means, power operated cable means trained over said pulley means and insertable through said counterweight sections, releasable means for securing the free end of said cable means below said sections whereafter said cable means may be used for raising and lowering said sections to and from said frame means, pin means insertable through said Iside bars for selectively locking one of said sections to said frame means after the sections have been raised to the latter, said power operated cable means being operable to lower the sections lying below the locked section from said frame means, and vertically extending bolt means for securing the sections retained in said frame means to the latter whereby said power operated cable means may be released for other operations when not employed for raising or lowering said sections.

5. For use in a vehicle having a main frame, a turntable mounted thereon for rotation in a horizontal plane, a boom assembly mounted on the turntable, and power operated cable means carried by the turntable and releasably connected to the boom assembly for actuating the latter, the combination of counterweight mechanism comprising frame means secured to the turntable, a plurality of counterweights adapted to be releasably connected with said power operated cable means, means carried by said frame means for connecting the power operated cable means with said counterweights whereby said power operated cable means is adapted to raise and lower said counterweignts to and from said frame means, and selectively operable means for securing a selectable number of said counterweights to said frame means whereby the power operated cable means may be released from said counterweights and employed for actuating the boom assembly when not employed for raising or lowering said counterweights.

6. For use in a vehicle having a main frame, a turntable mounted thereon for rotation in a horizontal plane, a boom assembly mounted on the turntable, and power operated cable means carried by the turntable and releasably connected to the boom assembly for actuating the latter, the combination of counterweight mechanism comprising generally inverted U-shaped frame means carried by the turntable, a plurality of counterweight sections, iirst means for securing said sections as a group to said frame means in vertical stacked relation, second means for selectively locking one of said sections to said frame means, and the power operated cable means being releasable from the boom assembly and connectable with said counterweight sections for lowering the sections lying below the locked section from said frame means when said first means is rendered inoperable.

7. For use in a vehicle having a main frame, a turntable mounted thereon for rotation in a horizontal plane, a boom assembly mounted at one end of the turntable and an opening in the other end of the turntable which in one position is adapted to overhang the main frame, and power operated cable means releasably connected to the boom assembly for actuating the latter, the combination of counterweight mechanism comprising generally inverted U-shaped frame means carried by the turntable above the opening therein and having vertical side bars, a plurality of counterweight sections shaped to be guided on said side bars, pulley means at the upper end of said frame means, the power operated cable means being releasable from the boom assembly and trained over said pulley means and insertable through said counterweight section, releasable means for securing the free end of the cable means below said sections whereafter the cable means may be used for raising and lowering said sections to and from said frame means through the opening in the turntable when the opening is in position overhanging the vehicle main frame, pin means insertable through said side bars for selectively locking one of said sections to said frame means after the sections have been raised to the latter, the power operated cable means being operable to lower the sections lying below the locked section from said frame means, and vertically extending bolt means for securing the sections retained in said frame means to the latter whereby the power operated cable means may be released from said counterweight sections and connected with the boom assembly for actuating the latter when not employed for raising or lowering said counterweight sections.

8. For use in a vehicle having a main frame, load handling means carried by said main frame, power operated means carried by said vehicle releasably connected with and adapted to actuate said load handling means, the combination of counterweight means secured to said frame means and including a counterweight for said load handling means, said counterweight being adapted to be releasably connected with said power operated means, means for connecting said power operated means with said counterweight means whereby said power operated means is adapted to raise and lower said counterweight relative to said main frame, and means for selectively securing said counterweight in one or" a plurality of positions against movement relative to said main frame.

9. For use in a vehicle having a main frame, a boom assembly mounted at one end of the vehicle, power operated cable means releasably connected to the boom assembly for actuating the latter, the combination of counterweight mechanism comprising generally inverted U-shaped frame means carried by the vehicle, a counterweight movable in said U-shaped trame for counterweighing the boom assembly and being adapted to be releasably connected with said power operated cable means, guide means for disposing the power operated cable means in raising and lowering relation with said counterweight, and means for selectively securing said counterweight against movement relative to said U-shaped trame.

References Cited in the iile of this patent UNITED STATES PATENTS 1,509,803 Brown Sept. 23, 1924 2,589,915 Wullschleger Mar. 18, 1952 2,674,378 Meyer et al. Apr. 6, 1954 

